I have completed all of the requirements of the Self-Driving Car Nanodegree Program and have officially graduated on February 11, 2019. In the last year two years, I have built projects in computer vision, deep learning, sensor fusion, localization, path planning, control, and system integration. I have worked so hard to complete projects and develop my skills. I am so proud of myself.
We trained a CNN model to predict steering angles from the visual input. Here is an example of our accomplishments.
We used the same CNN model on a different track to show the flexibility of this approach. The followings show as successful driving on a different track from one where the model was trained.
Source code can be found at https://github.com/jrkwon/mir_torcs
Unlike TORCS, Euro Truck Simulator 2 is a commercial product. The regular price is around $20. But as in the article below, an open source project, europilot (https://github.com/marshq/europilot) helps us to capture data for training.
We can use /dev/lidar instead of /dev/ttyUSB#. Refer the followings.
I used following references.
You need to change the Python version numbers if you are using different ones.
When an error message is shown from a python code using cv2 (opencv), the message is most likely misleading. The message is saying nothing but something is wrong. All the details in the message are not what you need to do to fix the problem.
I had issues with VideoCapture and imshow. The error messages look explanatory but they are not. All problems were stemmed from a python wrapper package that I installed through pip.
$pip uninstall opencv-python
Unlike scanf function family in MATLAB, C scanf doesn’t consider the comma(,) as a delimiter for the specifier “%s.”
Let’s say we have a data file as follows.
Spiderman,Parker,99<br />Superman,Ken,89<br />Batman,Wayne,79
The following code will not work. The variable “first_name” will have the whole line “Spiderman,Parker,99” since it thinks there is no delimiter in the line.
char first_name[50], last_name[50];<br />int grade;<br />FILE *fp = fopen("data.csv", "r");<br />fscanf(fp, "%s,%s,%d\n", first_name, last_name, &grade);
Here is a way to make scanf functions think the comma (,) is a delimiter.
fscanf(fp, "%[^,],%[^,],%d\n", first_name, last_name, &grade);
Unlike in C/C++, fscanf in MATLAB repeats the scanning as long as the formatted text matches. It is convenient but also confusing sometimes.
For example, in a text file there are lines as follows.
Image Width Height: 800, 600
Red X Y Radius: 200, 300, 300
Green X Y Radius: 300, 400, 200
Blue X Y Radius: 500, 500, 150
dim = fscanf(fid, '%*s %*s %*s %d, %d\n'); (a)
redc = fscanf(fid, '%*s %*s %*s %*s %d, %d, %d\n'); (b)
dim = fscanf(fid, 'Image Width Height: %d, %d\n');
redc = fscanf(fid, 'Red X Y Radius: %d, %d, %d\n');
grnc = fscanf(fid, 'Green X Y Radius: %d, %d, %d\n');
bluc = fscanf(fid, 'Blue X Y Radius: %d, %d, %d\n');
In Windows the Console doesn’t display any output from printf. Let’s see an example.
int main(void)
{
int i;
printf("Enter a number: ");
scanf("%d", &i);
printf("You entered %d\n", i);
return EXIT_SUCCESS;
}
These lines enforce stdout/stderr not to have buffers which means that all the output will be happening as soon as it takes place. One serious problem of this solution is that the program will be crashed if you start the debugger and try to step over any of printfs. So in the Debug mode, starting a new command prompt console is a good idea. Let’s me summary this workaround.
Put this function in your main function in the first place.
void set_std_buffer_off()
{
setvbuf(stdout, NULL, _IONBF, 0);
setvbuf(stderr, NULL, _IONBF, 0);
}
int main(void)
{
// turn off the std buffering
set_std_buffer_off();
// start your own code.
....
}
For the debug mode, use GDB command file.
Create a text file and named it as “gdbinit.txt” The file name is not important anyway. You may use any proper name. Open the text file and put this single line into the file and save it.
<span style="line-height:1.5em">set new-console on</span>
Open “Preferences” (Window > Preferences). Set the text file for “GDB command file:” in C/C++ –> Debug –> GDB. Click the “Apply” button and the “OK” button.
Try to debug your program. Then you will see a command prompt when the debugger starts. All outputs and inputs will be happening in the new command prompt without having any troubles.